Finding the Third Proportional to 12,786 and 19,770

Step by Step Solution

1. Step 1: Write the proportion equation
   12,786 : 19,770 = 19,770 : x
2. Step 2: Convert to fraction form
   12,786/19,770 = 19,770/x
3. Step 3: Cross multiply
   12,786x = 19,770 × 19,770
4. Step 4: Simplify right side
   12,786x = 390,852,900
5. Step 5: Solve for x
   x = 390,852,900/12,786
6. Step 6: Final answer
   x = 30,568.82